Sen. Lamar Alexander, center, and his wife, Honey, left, after he announced the start his “Standing Up for Tennessee” bus tour at Sullivan’s Restaurant in his hometown of Maryville, Tenn., July 25.

Associated Press

Sen. Lamar Alexander‘s polling shows him with a 30-percentage point lead over tea-party challenger Joe Carr in Tennessee’s Republican Senate primary, according to a polling memo prepared for the two-term incumbent’s campaign.

The poll, conducted by Republican pollster Whit Ayres from July 20-22 ahead of the state’s Aug. 7 primary, found Mr. Alexander leading Mr. Carr 53% to 21%. Mr. Ayres wrote that despite attacks against Mr. Alexander from Mr. Carr and longshot challenger George Flinn, Mr. Alexander’s stature among Tennessee GOP voters has remained stable.

“The fundamentals remain the same,” Mr.Ayres wrote in a memo for the campaign, obtained Monday by The Wall Street Journal. “60 percent or more of Republican primary voters like the job Alexander is doing and are likely to vote for him. About a quarter to a third don’t, and are not likely to vote for him. If that holds, it yields a very comfortable victory.”

Now for the caveats about internal polling released for public consumption: It is clear Mr. Alexander’s camp is trying to rebut a narrative that Mr. Carr is building momentum. The poll was conducted before two events last week that Mr. Carr’s camp touted as evidence of his momentum: Talk radio host Laura Ingraham traveled to Tennessee to host a rally for Mr. Carr and former Alaska Gov. Sarah Palin endorsed Mr. Carr via Facebook.

Internal polling has been justifiably viewed with much skepticism this primary season. It was only seven weeks ago that House Majority Leader Eric Cantor‘s (R., Va.) campaign leaked polling that showed Mr. Cantor leading unknown challenger David Brat by 30 points. Rep. Jack Kingston (R., Ga.) had polling before last week’s Georgia Senate runoff that showed him well ahead of David Perdue. Mr. Perdue is now Georgia Republicans’ Senate nominee. Mr. Brat is now every 2014 challenger’s patron saint.

The poll from last week showing Mr. Alexander ahead by an insurmountable margin is likely to be viewed with much skepticism.

“The last time an incumbent felt it necessary to release internal polling showing a double-digit advantage was Eric Cantor and we all know how that story ended,” said Mr. Carr’s campaign manager, Donald Rickard. “In recent weeks the Joe Carr for Senate campaign has earned the support of the Tea Party Patriots, Laura Ingraham and Sarah Palin so it’s unsurprising that Lamar Alexander’s campaign is desperate to project the idea of strength.”

A spokesman for Mr. Alexander declined to comment on the polling memo.

Mr. Alexander himself has taken moves to shore up his conservative bona fides ahead of Tennessee’s Aug. 7 primary. Last Thursday, he spoke on the Senate floor to warn that legislation proposed to prohibit sales of African elephant ivory across state lines could lead to President Barack Obama trying to “take away our guns.” On Monday, the Alexander campaign announced endorsements from Al Cardenas and David Keene, former chairmen of the American Conservative Union.

Whoever wins the Tennessee Republican primary is almost certain to carry the seat in the general election.

Mr. Ayres said in an interview Monday that Mr. Alexander remains popular and his challengers are relatively unknown.

“Lamar Alexander has been and remains a remarkably popular political figure in Tennessee as he has been for literally decades,” Mr. Ayres said. “That’s why it’s hard for challengers to gain the kind of traction against him that other challengers have gained in some other states.”

Mr. Ayres also recently served as the pollster for Sen. Lindsey Graham (R., S.C.), who won 56% of the primary vote against six GOP challengers.

Mr. Carr’s campaign, which has scarcely raised enough money to travel the state let alone conduct regular polling, two weeks ago trumpeted a poll funded by Tea Party Nation that showed Mr. Carr within seven percentage points of Mr. Alexander.

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